1. Field of the Invention
The present invention relates to an accessory-grip, which is detachably attached to a camera body.
2. Description of the Related Art
Conventionally, a camera has various kinds of electric circuits, to which electric power is supplied from a battery mounted in the camera body. Exhaustion of the battery changes, depending upon the conditions under which the camera is used. For example, when constantly or even commonly performing a photography with an electronic flash, the life of the battery is drastically shortened, and thus the battery has to be changed quite often. Therefore, a camera is proposed, in which an accessory-grip housing batteries, the number of which is greater than that in the camera body, is detachably attached to the camera body, so that the camera can be used for a long time without changing the batteries.
In a usual photographing state, a camera body is set to a horizontal position, in which the shutter button is positioned at the upper-right of the camera body when being used by its operator, i.e., when seen from the rear of the camera. Depending on the photographic object, the camera may be set to a vertical position in which the camera body is rotated from the horizontal position about the optical axis of the photographing optical system. When the camera is set to the vertical position, however, the shutter button is positioned at an upper portion of the left surface of the camera body when viewed by the user. This causes an awkward shutter release operation. Therefore, a camera has been proposed, in which, separate from a first shutter button provided on the camera body, a second shutter button is provided on an accessory-grip housing a battery in such a manner that the second shutter button is positioned at the upper-right when viewed by the user, similarly to that in the horizontal position.
In the conventional accessory-grip, the housing is connected to an internal thread of a tripod provided on the bottom surface. Namely, the accessory is provided with an external thread with which the internal thread is screwed, and a dial, attached to the external thread member, projects from a side surface of the accessory-grip, so that the accessory-grip can be attached to and detached from the camera body, by rotating the dial. However, in the attaching and detaching operation, the dial has to be rotated several times, which is cumbersome and takes time. Further, in the detaching operation, since it is not easy to recognize whether the external thread is released from the internal thread, the accessory-grip may accidentally drop off from the camera body at the moment the external thread releases from the internal thread.
Therefore, an object of the present invention is to provide a lock device in which attaching and detaching operations of an accessory-grip of a camera are simplified and that prevents the accessory-grip from accidentally dropping from the camera body.
According to the present invention, there is provided a device for locking an accessory-grip to a camera body, the device comprising a housing, a lock lever, and first and second connecting members.
The lock lever is movably supported by the housing. The lock lever is moved at least between a lock position and a partial release position different from the lock position. The first and second connecting members are movably supported by the housing, and can be displaced in association with the lock lever. The first and second connecting members are engaged with the camera body, when the lock lever is positioned at the lock position. The first connecting member is released from the camera body while the second connecting member continues to be engaged with the camera body, when the lock lever is positioned at a partial release position.
The lock lever may project from a guide slot formed in the housing and be movable along the guide slot. In this structure, dust or foreign matter may enter the housing through the guide slot.
Therefore, another object of the present invention is to provide a lock device in which dust and foreign matter are prevented from entering the housing through the guide slot.
According to the present invention, there is provided a device for locking an accessory-grip to a camera body, the device comprising a housing having a guide slot, a lock lever, and a lever curtain.
The lock lever is provided for locking the accessory-grip to the camera body and releasing the accessory from the camera body. The lock lever projects from the guide slot and is movable along the guide slot. The lever curtain is provided to a periphery of the guide slot to cover the guide slot and allow the lock lever to move along the guide slot.